The van's driver blasted the horn and then, after hesitating, finally braked as crossing monitor Elisa Salinas entered the crosswalk on Clark Street directing a "STOP" placard toward traffic. With her other hand, she signaled to waiting children that she wasn't ready for them to step off the curb yet.

"Some cars will not stop, even if they see little kids," said Salinas, who has been volunteering for six years as a crosswalk monitor at Hayt Elementary School in Chicago's Edgewater neighborhood on the Far North Side. As she spoke, the driver glared at her while waiting for the children to cross.

Salinas, mother of two Hayt students who said a car nearly struck her the previous week, has become accustomed to close encounters.

From 2007 through 2011, nearly 1,700 youths, ages 5 to 18, were struck by vehicles in Chicago within about a block of a school, according to a Tribune analysis of the most recent accident data the city reported to the state. Youths involved in accidents near schools represent an average of about 10 percent of all pedestrians hit by vehicles in the city over the five-year period.

Citywide, about 22 percent of the approximately 16,500 vehicle-pedestrian crashes over the five-year period involved injuries to youths, the accident reports show. The data show no improvement from an earlier city study that found, on a per capita basis, children ages 5 to 18 are more likely than adults to be involved in pedestrian crashes.

The number of near-collisions runs much higher. Experts consider such incidents warning signs, signaling that the potential for tragedy is high and that city streets are not safe for children.

"There is a bit of a culture of reckless driving, of not taking seriously that your car could be a coffin on four wheels if you are not responsible," Chicago transportation Commissioner Gabe Klein said.

He acknowledged that Chicago hasn't come close to Washington, D.C., and a few other metropolitan areas in reducing fatal crashes involving pedestrians, despite ongoing efforts here to carry out a pedestrian safety program, step up enforcement of traffic laws and introduce traffic-calming strategies.

"This is a multipronged holistic process, and it will take a number of years. But we expect gains in Mayor (Rahm) Emanuel's first term," Klein said, adding that it will be impossible to attract families with children to live in the city if the streets are deemed unsafe.

Pedestrian fatalities in Chicago hit a 17-year low in 2010 with 32 deaths, including eight school-age children, down from 88 pedestrian deaths in 1994, according to the Illinois Department of Transportation.

But 48 pedestrians were killed in vehicle crashes in the city last year, according to a preliminary count that is subject to change, provided last week by the Chicago Police Department.

Vehicle-pedestrian crashes have totaled about 3,000 a year in Chicago for a number of years. A federally funded study that the Chicago Department of Transportation released in 2011 found that 80 percent of fatal and serious crashes occurred within 125 feet of the midpoint of an intersection — at crosswalks or nearby.

The most recent data available indicate that locations on the West and South sides are hot spots for vehicle-pedestrian crashes involving youths and teenagers.

Intersections and corridors that the Tribune identified from the data as being among the top danger zones for school-age Chicagoans include Ashland Avenue and 79th Street; the majority of Central Avenue in the Austin community; Chicago and Laramie avenues; Cicero Avenue around West Ohio Street and West Race Avenue; Pulaski Road and 79th Street; King Drive and 63rd Street; Pulaski and Jackson Boulevard; and 103rd Street around Corliss and Cottage Grove avenues.

Studies have suggested numerous possible reasons for the high concentration of crashes between pedestrians and vehicles in poorer neighborhoods, which typically have much less foot traffic than central business districts.

"In some of these blighted neighborhoods with a lot of vacant properties, traffic speeds tend to be higher because there is less commerce, fewer reasons to slow down and stop," said Ian Savage, an economics and transportation professor at Northwestern University.

But there are many other possible factors, Savage said. In poor neighborhoods, generally more people walk than drive, he said. Also, suburban drivers travel through low-income neighborhoods en route to downtown and other popular destinations in Chicago, Savage said. The increased volume of drivers, coupled with the fact that most are passing through and trying to cut travel times, may contribute to the high number of pedestrian crashes, he said.

Savage said he doubts that pedestrians in low-income neighborhoods are more careless than pedestrians elsewhere. And no evidence exists to support the idea that driving styles are more aggressive in impoverished neighborhoods, he said.